I can't think of its name, but get off the Argyle stop on the red line, turn left, cross the street and there is a good grocery about a block away. I stock up there. The prices are great, but the selection is often confusing. They have about 60 different kinds of noodles, about 100 sauces, and some products I can't identify. Fresh crab and seafood too, as well as various rices in packages up to 100 lbs. You gotta figure it out for yourself, though. There ain't much customer service going on there.
Re: Vietnamese grocers
You want to concentrate your efforts on Arglye Street (and the surrounding area) in Uptown.
1. Trung Viet -- 4936 N. Sheridan, 773.561.0042
2. Hoa Nam -- 1101 W. Argyle, 773.275.9157
3. Viet Hoa -- 1051 W. Argyle, 773.334.1028
4. Vinh Tho -- 1112 W. Argyle, 773.275.2985
5. Sea World Food -- 1130 W. Argyle, 773.334.5335
6. Tai Nam -- 4925 N. Broadway, 773.275.5666
7. Thai Grocery -- 5014 N. Broadway, 773.561.5345
8. Thailand Food Corp. -- 4821 N. Broadway, 773.728.1199
9. Broadway Supermarket -- 4879 N. Broadway, 773.334.3838
10. Golden Pacific Market -- 5353 N. Broadway, 773.334.6688
I cook ALOT of Thai and Vietnamese food at home so I am well-aquainted with all of the shops listed above, but my strongest recommendations are reserved for Thai Grocery, Thailand Imports, Hoa Nam and Tai Nam.